In an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) of a third-generation mobile communications Long Term Evolution (LTE) system, uplink data are transmitted through a Physical Uplink Shared Channel (PUSCH). An uplink radio resource is allocated to each User Equipment (UE) by an Evolved NodeB (eNB). An access technology adopted by the E-UTRAN is the Orthogonal Frequency Division Multiplexing (OFDM) technology; radio resource management of an E-UTRAN system, compared with a second-generation mobile communications system, is featured by a large bandwidth and a multiple time threads; the radio resource of the E-UTRAN system is presented both on time domain and frequency domain, thus the number of users which the radio resource can bear is largely increased.
A Radio Resource Control (RRC) layer of the LTE system may send a RRC message to realize many operations, such as, establishing the RRC layer link between the UE and the eNB, configuring a system parameter and passing a UE capability parameter. Wherein, the downlink RRC message is sent on a Physical Downlink Shared Channel (PDSCH). Some system-related common parameters, such as the frequency of a cell, the system bandwidth of the cell and other information, are sent to all UEs in the cell by the eNB through a broadcast message, wherein the broadcast message is sent on a Physical Broadcast Channel (PBCH).
For allocating resources and providing services to each UE according to the requirement of the UE, so as to realize better multiplexing performance in uplink transmission, and also for making full use of the system bandwidth flexibly and efficiently, the LTE system formulates a specific control message for uplink transmission resource allocation of the user. Wherein, the control message which dedicated to performing resource allocation for the PUSCH is sent to the UE by the eNB, and the control message for the resource allocation is also called Uplink Grant (UL Grant), wherein the UL Grant is sent on a Physical Downlink Control Channel (PDCCH).
In order to ensure reasonable radio resource allocation for each UE, the LTE system requires the UE to report the data status in the buffer of the UE, and the report is reported to the eNB in form of a Buffer Status Report (BSR). In the LTE system, the Logical Channels (LCHs) of the UE are divided into 4 Logical Channel Groups (LCGs) according to the priority; the BSR contains the group number of each LCG, and the buffer size index which indicates the amount of data to be transmitted over all the LCHs in the LCG. The buffer size index reported in the BSR is obtained by inquiring on a preset table by the UE according to the actual amount of data to be transmitted over all the LCHs in the LCG; the buffer size index of each LCG is represented with 6 bits and 64 buffer size indexes can be represented; a buffer size index table predefined by the LTE system is shown in Table 1 (BSR table1),
TABLE 1IndexBS value [bytes]0BS = 01 0 < BS <= 10210 < BS <= 12312 < BS <= 14414 < BS <= 17517 < BS <= 19619 < BS <= 22722 < BS <= 26826 < BS <= 31931 < BS <= 361036 < BS <= 421142 < BS <= 491249 < BS <= 571357 < BS <= 671467 < BS <= 781578 < BS <= 9116 91 < BS <= 10717107 < BS <= 12518125 < BS <= 14619146 < BS <= 17120171 < BS <= 20021200 < BS <= 23422234 < BS <= 27423274 < BS <= 32124321 < BS <= 37625376 < BS <= 44026440 < BS <= 51527515 < BS <= 60328603 < BS <= 70629706 < BS <= 82630826 < BS <= 96731 967 < BS <= 1132321132 < BS <= 1326331326 < BS <= 1552341552 < BS <= 1817351817 < BS <= 2127362127 < BS <= 2490372490 < BS <= 2915382915 < BS <= 3413393413 < BS <= 3995403995 < BS <= 4677414677 < BS <= 5476425476 < BS <= 6411436411 < BS <= 7505447505 < BS <= 878745 8787 < BS <= 102874610287 < BS <= 120434712043 < BS <= 140994814099 < BS <= 165074916507 < BS <= 193255019325 < BS <= 226245122624 < BS <= 264875226487 < BS <= 310095331009 < BS <= 363045436304 < BS <= 425025542502 < BS <= 497595649759 < BS <= 582555758255 < BS <= 682015868201 < BS <= 798465979846 < BS <= 9347960 93479 < BS <= 10943961109439 < BS <= 12812562128125 < BS <= 15000063BS > 150000
wherein, Index represents the buffer size index, BS value represents the amount of date corresponding to the buffer size index; when reporting the BSR, the UE inquires on the table according to the amount of data to be transmitted over all the LCHs in the LCG, and reports the corresponding buffer size index.
According to the result obtained by inquiring on Table 1, the buffer size index of each LCG, which is reported in the BSR, is applicable to a LTE single-carrier system. In order to meeting the requirements of various fast-growing wireless services at present and in future, the process of developing a next evolution standard, namely the LTE-Advanced standard, of the LTE system has been started.
The LTE-Advanced system is a standard LTE-Advanced system developed by the 3rd Generation Partner Project (3GPP) organization to meet the International Mobile Telecommunication-Advanced (IMT-Advanced) requirement of the International Telecommunication Union (ITU); it is an evolved version based on the LTE release 8 system; it introduces many new technologies to meet basic requirement of the IMT-Advanced, wherein the most important technology is carrier aggregation.
Because of the shortage of wireless spectrum resource at present, the spectrum resources owned by the mobile providers all over the world are usually scattered; the IMT-Advanced requires higher peak rate (supporting 100 Mbps under high mobility, and supporting 1 Gbps under low mobility), but the maximum bandwidth of the current LTE standard, namely 20 MHz, cannot meet the requirement of the IMT-Advanced, so it is required to expand to a higher bandwidth, for example, the Frequency Division Duplex (FDD) supports 80 MHz at most, and the Time Division Duplex (TDD) supports 100 MHz at most, thus the amount of data that the UE can transmit is also increased by several times, compared with the LTE. Except expanding the bandwidth, in order to achieve a higher rate, Multiple-Input Multiple-Output (MIMO) is also a core technology for improving throughput of the LTE-Advanced system. Taking the early version of the LTE-A system as an example, considering the increase of the uplink bandwidth (which is five times of the LTE bandwidth) and the uplink double-carrier MIMO (which is twice of the LTE single-carrier) together, in the early version of the LTE-A system, the uplink rate of the UE is improved to be 10 times of that of the LTE system.
As shown in Table 1, the BSR table preset in the LTE system can only granularly represent the maximum data of 150K, all the other services with traffic more than 150K belong to the same BSR grade (Grade 63); after the data traffic of the LTE-A system is improved, if the BSR table preset by the LTE system is still used, then the LTE-A service with large throughput will cause that the network is not able to distinguish the buffer status of the UE from 150K to 1500K, so that it impossible to allocate resource reasonably and effectively.